The invention disclosed herein relates generally to improved identification of media identifiers.
Removable media storage devices such as tape libraries, optical libraries, and CD-ROM jukeboxes are frequently used for storage of electronic data generated by client computers. A removable media storage device generally includes removable media such as tape cartridges, optical disks, or CD-ROMS and may also include a mechanism, such as a robotic arm, that moves the removable media into and out of a drive where content of the media may be read or updated.
Removable media may include an identifier which may be affixed to the media, such as a hand printed label, machine-readable barcode, or other identifier. The media identifier generally contains information naming, indicating, distinguishing or otherwise identifying the media. The use of barcodes to identify removable media allows storage devices to operate autonomously with greater efficiency. For example, a removable media storage device equipped with a barcode reader may identify and select a removable media for a storage operation based on the respective barcode. A storage device with a barcode reader may automatically identify a specific item of removable media according to the barcode thereon and insert the removable media in a corresponding drive to perform a storage operation. Thus, a storage operation can proceed according to predefined schedules and criteria with minimal operator intervention resulting in greater efficiency.
There are several types of barcodes. In general, a typical barcode includes a series of vertical lines or other graphical indicators which correspond to a code comprising alphanumeric characters. Barcodes can be read by optical scanners which scan the vertical lines forming a barcode. Barcodes applied to media are generally a standard length, such as six or eight characters, which may be in accordance with ANSI/AIM standards.
Some optical scanners that read barcodes may be capable of reading only one type of barcode, or only barcodes of a particular length. When a new media item, such as a tape cartridge, optical disk, or CD-ROM is added to a storage device that has such an optical scanner, the media identifier information may not be readable by the scanner. This may occur when using new barcoded media items in a legacy storage device. For example, an older scanner in the legacy storage device may not be equipped to process new barcodes. To avoid such problems, a storage management systems may be limited to using certain barcoded media, or alternatively, the optical scanner may be replaced or upgraded.
In addition to scanner limitations, there may be problems with labels or fields of view for scanners that cause a scanner to read a media identifier incorrectly. For example, a media identifier may lie outside of a field of scan, and portions of the identifier may not be scanned, or a media identifier may be damaged, misaligned or otherwise unreadable. For example, a label including a media identifier may be worn or placed in a position that may prevent the optical scanner from reading the media identifier in its entirety. Thus only a portion of the identifier is read and the media cannot be identified.